Possible olfaction-based mechanisms in human kin recognition and inbreeding avoidance

J Exp Child Psychol. 2003 Jul;85(3):279-95. doi: 10.1016/s0022-0965(03)00061-4.


Three studies explored kin recognition through olfaction. In Study I, adults (N=22) were tested for ability to identify the odors of themselves; their mother; their father; a sister; a brother; a familiar, unrelated individual; and a stranger. Acquaintances were identified as accurately as biological kin, implicating an association mechanism. However, biological kin were often confused, implicating phenotypic matching. Same-sex kin were confused more than opposite-sex kin, but mainly when same-sex kin had odors of similar intensity. Study II implicated phenotypic matching. Mothers (N=18) could identify their biological children but not their stepchildren. The preadolescent children (N=37) identified their full siblings but not half-siblings or stepsiblings. Thus, olfactory cues may help mediate favoritism of blood relatives. In Study III, mutual olfactory aversion occurred only in the father-daughter and brother-sister nuclear family relationships. Recognition occurred between opposite-sex siblings but not same-sex siblings. Thus, olfaction may help mediate the development of incest avoidance during childhood (the Westermarck effect).

MeSH terms

  • Adult
  • Biological Evolution
  • Choice Behavior
  • Consanguinity*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Phenotype
  • Pheromones / physiology
  • Psychological Theory
  • Recognition, Psychology*
  • Sexual Behavior / physiology*
  • Smell / physiology*


  • Pheromones